.sl-left {
    margin:0px;
    background: url("../img/login_bg.png") no-repeat;
    background-size:100% 100%;
    height: 100vh;
}


.sl-right {
    display: flex;
    /* 启用flex布局 */
    justify-content: center;
    /* 水平居中 */
    align-items: center;
    /* 垂直居中 */
    height: 100%;
}

.sl-right .main-box {
    margin-top: 150px;
    height: 500px;
    width: 500px;
}

.sl-right .login-form input {
    width: 100%;
    padding: 10px;
    margin: 10px 0;
    border: 1px solid #ccc;
    border-radius: 4px;
}

.sl-right .login-form button {
    width: 100%;
    padding: 10px;
    border: none;
    background-color: #495057;
    color: white;
    border-radius: 4px;
    cursor: pointer;
}

.sl-right .login-form button:hover {
    background-color: #343a40;
}

.sl-right .login-form .alternative {
    text-align: center;
    margin-top: 20px;
}